Diesel oil is obtained from crude oil in substantially the same manner as most other petroleum bi-products, such as gasoline, distilled therefrom. Each such bi-product has its own boiling point and is obtained by separating it from the other components of the crude oil by condensing it from the main crude distillate at a predetermined temperature.
Modern, crude oil refining technology has failed to isolate many of the hydrocarbons at each distillation stage and, as a consequence, diesel oil is collected as a condensate contaminated with both lighter and heavier hydrocarbons, various types of aromatics, benzenes, dioxins and, in certain circumstances, particulate material.
Also, the collected diesel oil can be contaminated with water whose content can be increased during subsequent storage, transportation and distribution of the diesel oil.
Efforts to remove these contaminants by, say, heating or chemical reacting the collected diesel oil have been substantially unsuccessful, mainly because the chemical composition and/or physical properties of the diesel oil itself tend to be changed as a result.
Although unwanted particulates in diesel oil are generally extremely small, they still tend to have an abrasive effect on the various components, such as, injectors, exhaust valves, pistons and cylinder walls, of diesel engines. Also, these particulates tend not to burn with the diesel oil during the combustion process and, as a consequence, the power ratios of the diesel engines are correspondingly decreased and the level of harmful exhaust emissions is correspondingly increased.
Further, harmful exhaust emissions, resulting from the combustion or partial-combustion of other diesel oil contaminants, such as at least some of those discussed above, can lead to undesirable atmospheric pollution.
Chemical additives, whether synthetic or natural, can be used in diesel oil as so-called "masking agents", in an attempt to eradicate the problem of pollution caused by the fully or partially combusted contaminants inherent in diesel oil. However, it has been found that these chemical masking agents only help to create other pollution problems when exhausted to the atmosphere after the combustion process.